Supporting the Mac OS menubar in JavaFX

[Jim Graham]

If this was simply a skinning technique of "moving the Stage's menubar 
to the screen's menubar" that works if you have a window open, but it 
doesn't solve the problem of what happens when you have no windows open 
when Mac applications typically still manifest menus in the screen menubar.

Sticking a "separate but equal" menubar somewhere would lead to 
applications failing to look like native Mac apps until the developers 
are made aware of the issues and require "extra" coding to deal with Mac 
deployment.

If we could provide a way to specify:

- Here are the menubar items that apply to all windows.
- Here are the additional menubar items that apply to a specific window.
- To be most flexible, the "additional items" might have to be 
additional items in the top-level menus that were specified for all windows
- Would there also be a need to specify "but not these items" for some 
windows to delete some items that only make sense when no windows are open?

Then it would be both an API for letting the runtime know which menubar 
items should remain after the last window closes on Mac, and a way to be 
able to populate lots of window menubars when an application has 
multiple windows.

The actual manifestation of the menubar would be a control, but the 
specification of what items are needed could be in an independent format 
that doesn't bring in a whole new package.  We could create skeleton 
"menu-ish-bar-ish-item" classes in the application package and those 
could be the data that the Menu* controls take, but one could attach a 
list of those to an Application object without having Application depend 
on controls.  A Stage could then take an additional list and combine it 
with the list on the Application to make the full menu bar list which is 
then skinned by the controls.

When no windows are open, then the Mac-specific application could still 
skin them in a native skin and deploy them on the screen menubar, or 
have a hidden dependency on the controls for that platform only.

That's a fairly loose conceptual hand-waving outline, but maybe it could 
dislodge a more concrete design from someone more familiar with how all 
of those objects interact?

			...jim

On 12/9/2011 3:46 PM, steve.x.northover at oracle.com wrote:
> Many toolkits have supported portabilitly between Mac and Windows (and
> other operating systems that put the menu bar in the window) by swapping
> the menu bar on stage focus in and out. This is what SWT does. Recently,
> an app wide menu bar was added to support the Mac.
>
> Steve
>
> On 09/12/2011 6:34 PM, Tom Schindl wrote:
>> [...]
>>
>>> Another place to specify a MenuBar would be on Stage, rather than (or in
>>> addition to), Application. Having a MenuBar property on Stage would
>>> allow for the MenuBar to change based on the currently focused Stage -
>>> but I'm not certain this is desirable or even the expected behaviour of
>>> Mac OS. Therefore, I'm thinking that this is not likely to happen unless
>>> we hear otherwise.
>> Well the menu changes definately based upon the focused top-level
>> window. So I'm quite sure the MenuBar has to be specified on the Stage
>> not?
>>
>> I'm wondering though how you'd like to support all the themeing stuff
>> one is able to apply on menus/menuitems on OS-X.
>>
>> IIRC I recently read in a mail from Mike Swingler that one can implement
>> arbitary Java Drawing post-Leopard but I'm not sure that matches the
>> OS-X Menubar idea and all the fancy things one can do with JavaFX.
>>
>> Tom
>>